World’s first potato-chip sandwich café

Crisps—otherwise known as potato chips—aren't just for snacking anymore. The world's first "crisp sandwich" café opened, where customers can gorge on sandwiches made out of something different from the regular ham and cheese.

Inspired by an article on parody news website The Ulster Fry, Simply Crispy in Belfast, Northern Ireland opened its doors on Monday.

The pop-up café has already proven successful, having sold out of the crisp sandwiches only two hours after opening.

However that wasn't the main question on people's minds—in an interview with the U.K.'s "Channel 4 News", café owner Gary Keery was questioned as to the rationale behind selling a small bowl of cereal for £2.50 ($3.80) in one of London's poorest boroughs.

Rendle added that the fact that pop-up cafés may only be open for a limited time "adds to the novel experience, which combined with the right social media attention can generate a 'buzz' that may not be sustainable, but attracts a much higher level of interest."

However, permanent cafes like London's cereal café "will have to gain a loyal following to remain afloat," and make sure they maintain it.

"Crisp sandwiches represent the alternative or the 'anti-pret' offering to the chained bakery fast food industry. Some consumers might think it is a gimmick, others the return of no-nonsense food," said Rendle.

However, crisps are high in saturated fats and salts and have been subject to a high-profile campaign by the British Heart Foundation to discourage over-consumption. The charity's "Food4Thought" campaign in 2006 revealed that half of U.K. children ate a packet of crisps per day, which was compared to drinking nearly five liters of oil every year.